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By R. Gallinger

In 1997, a group of Canadian mining companies met to review the Mine Environment Neutral Drainage (MEND) program and to consider future activities. They concluded that (1) that Canadian industry and Natural Resources Canada (NRCan) should fund a small secretariat in Ottawa to support technology transfer in Canada and, (2) that it was important for industry to continue the momentum of MEND on an international scale. The need for the International Network for Acid Prevention (INAP) was strongly endorsed by consultants, company, university, and government experts from Australia, Canada, and the United States who convened in Vancouver in February 1998. The initial focus was the development of a solid knowledge base covering the collective experience of INAP?s members to promote the dissemination of successful practices, the identification of knowledge gaps, and the formulation of effective research proposals. The sharing of information on past successes and failures alone was viewed as sufficient justification for the formation of INAP. INAP was officially launched in October 1998, and is now an effective, industry-based initiative to globally coordinate research and development in the management of sulphide mine waste. Significant improvements in the management of sulphidic mine materials through knowledge sharing, research, and development of technology by INAP will reduce liability associated with acid drainage. This paper will explore the international efforts and activities of INAP

May 1, 2005

By R WOODS

The interaction of, flotation collectors with sulphide mmerals takes place at the solid-solution interface. The electrochemistry of the processes which affect this interface are discussed. The interaction of xanthates with sulphides is an electrochemical process, xanthates being electro-oxidized to chemisorbed xanthate and dixanthogen.The role of oxygen is to provide a cathodic process to allow the anodic oxidation to occur. The hydrophobic condition of the mineral surface is brought about by the presence of the oxidized xanthate species. The action of reagents which can activate or depress the flotation of sulphides is discussed briefly.

Jan 1, 1972

By H. P. Jacobi

"INTRODUCTIONPine Point Mines, operated by Cominco Ltd., is located approximately 65 miles east of Hay River, N.W.T. on the south shore of Great Slave Lake.The milling operation started in the fall of 1965 with a capacity of 5,000 tpd. An addition was put into operation late in 1968 to bring the nominal capacity up to 8,000 tpd. The present milling rate is 11,000 tpd.With a feed grade of approximately 2.9% Pb and 6.0% Zn the annual concentrate production amounts to roughly 130,000 SDT of lead concentrate and 370,000 SDT of zinc concentrate for a total of 1/2 million tons of product.This tonnage is moved by railroad. Pine Point is served by the Great Slave Lake Division (G.S.L.) of the Canadian National Railways which connects to the Northern Alberta Railway System (N.A.R.) at Roma Junction, at Peace River, Alberta. The system in turn connects to the CNR and the CPR in Edmonton, Alberta. From here the concentrates move inland chiefly to Trail, B.C., with some shipment to other Canadian and U.S. smelters, and to the port facilities of Pacific Coast Terminals at New Westminster, B.C. for offshore export.This paper will focus on the problems associated with the movement of lead and zinc concentrates from Pine Point to port facilities on the west coast."

Jan 1, 1975

By M. L. Fenger

This report describes a study of the factors which affect medium voltage (661 - 1000 volts) and high voltage (1001 - 7500 volts) trailing cable couplers for use in underground coal mines to connect trailing rabies. Improvements in quality, dependability, and safety of medium and high voltage couplers are presented in the form of requirements for couplers. The results of an investigation of high voltage trailing cable coupler design and of whether trailing cable couplers must have a metallic shell as required by CFR 30 part 75.805 are presented. Conclusions and recommended research programs are included that describe the present situation and future development approaches.

Jan 1, 1978

By Andy Davis

The evolution of pit lake water quality depends on the lithology and hydrologic characteristics of the ultimate pit surface, the availability of buffering capacity in the wall rock vs. oxidizable sulfide content, the alkalinity of recharging groundwater and the evapoconcentrative characteristics of the system. This paper assesses the geochemistry of 11 existing pit lakes, ranging from the acid Red Hill and Berkeley pit lakes (pH 2.6 to 2.8) to the alkaline Yerington pit lake (pH 8.45). Predicted pit lake chemistry is similar to that in existing pits, with long-term chemistry lying on a geochemical continuum between end members that consist of influent calcium bicarbonate groundwater and naturally occurring sulfate-rich evaporate playa lakes.

Jan 1, 1997

By James A. Bachmann, Christopher J. Gray

On December 26, 1994, at 1:00 am, Santa Fe Pacific Gold's Twin Creeks Mine experienced a major highwall failure involving over 2.5 million tons. The resulting effects of this slide were thousands of ounces of gold that were now deferred and an unstable wall above which made mining the slough material unsafe.

Jan 1, 1996

By M. Wang, Z. Sui, T. Lou

After smelting, the associated mineral ore accompanying Valuable Metal Compounds (VMC),such as titania and borate in BF., most of the VMC were separated from the metal into the molten slag that is an associated slags. Based on several case studies in laboratories and in a practice in a pilot plant on the associated slags , there occur a feasibility to recovery VMC from the slags by anew process- Selective Precipitation Technique (SPT) on which three continuous steps are involved: (1) The selective enriching the dispersed VMC into a designed mineral phase in the molten slag; (2) The selective coarsening the designed mineral phase with large crystal grain size;(3) The selective separating the coarsen phase from tailing by mineral dressing or hydrometallurgical process . Some results on the recovering the VMC from the associated slags by SPT were summarized as examples in present paper. Keywords: selective precipitation technique, associated slag, recovering metals from slag.

Jan 1, 2004

By L. A. Haas

In this Bureau of Mines investigation, conditions were determined to form an iron sulfide adherent coating with a metallic golden luster on steel upon anaerobic heat treatment with sulfur. The sulfide formation rate was determined in the temperature range of 105° to 500° C with reaction times up to 68 hours. The optimum temperature and time to form an adhering decorative coating on mild steel was in the range of 105° C for about 70 hours to 285° C for 1 hour. The golden coating consisted of an inner layer of pyrrhotite and an outer layer of pyrite. At temperatures higher than about 300° C, the outer layer thickness decreased owing to the decomposition of pyrite to pyrrhotite.. Small quantities (<0.5 wt-pct) of petroleum oil accelerated the sulfide growth rate. The sulfide coating decreased the corrosion rate of steel in a neutral aqueous medium by a factor of two. The dissolution of pyrite in water was dependent on particle size and surface area with the flat pyrite coatings exhibiting the lowest dissolution rate.

Jan 1, 1974

By Henry John Luna Córdova

El presente trabajo describe el proceso de gestión de calidad en la administración de los derechos mineros a través de la automatización de procesos desarrollados por el Instituto Nacional de Concesiones y Catastro Minero (INACC) organismo público descentralizado del Sector Energía y Minas que administra el Procedimiento Ordinario Minero para el otorgamiento de Concesiones Mineras, el Catastro Minero Nacional y la distribución del Derecho de Vigencia a escala nacional. Entre otras funciones de dicha institución está la creación de una serie de base de datos numérica, que le han permitido optimizar dichos procesos en calidad. Así como en el aspecto de la administración del Derecho de Vigencia y Penalidad, se creó el software para automatizar sus procesos y efectuar el cobro respectivo en las entidades del sistema financiero nacionall. Finalmente en el aspecto catastral, se generalizó el uso de coordenadas UTM (PSAD56) para identificar los derechos mineros, asimismo, se crearon los parámetros de transformación de coordenadas WGS84 a UTM.

Jul 31, 2003

By A. K. Singh

Between the main fan and the coalface in a mine a lot of air is lost through leakage at stoppings, doors, air-crossing etc. so that a much larger quantity of air has to be circulated by the fan in order that the stipulated quantity of air reaches the face. Stoppings are of vital importance not only for effective ventilation of underground mines but also for isolation of areas affected by fire or susceptible to spontaneous heating. Generally, isolation stoppings are made of brick in cement mortar. If the area is far from the pit or unapproachable, it is very difficult and sometimes impossible to build these stoppings. To overcome these difficulties, particularly near fire affected zones, an alternate successful attempt was made in Indian mines to make a plug underground, from surface through borehole, using cement concrete. In this paper the salient features of the methodology adopted for construction of the plug and the experimental procedure for the measurement of air leakage by SF6 tracer gas is described. Measurements of air leakage through rows of ventilation stoppings in two mines viz. Moira (Jambad and Kajora seams) and Kuardi11/12 (Niga seam) collieries of Eastern Coalfields Ltd. (ECL) have been incorporated. Results of experiments conducted at the Central Mining Research Institute (C.M.R.I) to determine leakage through25 and 38 cm thick brick stoppings are also discussed. Results of all these studies are compared, which show that the efficacy and reliability of the remote filled cement concrete plug in respect of air permeability is satisfactory.

Jan 1, 2004

By M. Shapiro, L. A. le Grange, B. Henning

A paper was presented by Bateman Minerals and Metals at INFACONX (2004) describing a simplified Computational Fluid Dynamics (CFD) Model for predicting the temperature and velocity distributions in all the fluid zones of a single electrode DC Furnace simultaneously with the temperature distributions in the refractory lining of the vessel. The boundary conditions imposed on the model consisted of the arc current, external surface film coefficients and ambient temperatures. The temperature and velocity distributions in the free-board, slag and metal were solved simultaneously by coupling across the interfaces between the fluids and transportation phenomena developing in the plasma arc. A simplified model was used to describe the ex-change of energy by radiation between the arc and surfaces enclosing the freeboard region. The strengths of this model were reported as being the ability to: ?Solve the different zones and transportation phenomena simultaneously without the need to transfer partial numerical results between different numerical analysis applications. ?Solve velocity and temperature distributions without assumptions regarding internal film coefficients and additional internal temperature boundary conditions. One of the disadvantages of the model was that the energy absorbed by the process was not modelled, resulting in vessel performance predictions under heat loss conditions only. Whilst this allowed potential problem areas such as localized refractory heating to be identified, the model was only capable of predicting how these could be improved by varying the overall geometry and materials of construction. This paper presents improvements in the application software and user defined subroutines of the model as follows: ?Incorporation of surface to gas, gas to gas and gas to surface radiation models to improve the accuracy of radiative heat transfer mechanisms within the freeboard. ?Incorporation of a process energy absorption model based on a theoretical temperature dependant enthalpy curve which incorporates melting, smelting and superheating in selected areas of the bath. This enables the effect of feed distribution and power to feed ratio changes to be estimated. The effects of a commercial arc at full power on the freeboard and slag can now be simulated with increased accuracy.

Jan 1, 2007

By Frederic Benard

PRIOR to 1936, the Ontario Refining Co. received all incoming blister copper from The International Nickel Company&apos;s smelter in the usual form of 460-lb. cakes, or slabs. These were received in open cars in lots of 250 pieces. At the refinery the cakes were unloaded onto narrow-gauge cars, for convenient handling and pickup by charging cranes. In March 1936, an investigation was started on the feasibility of transferring converter copper in the molten state from the smelter to the refinery anode furnaces, a distance of 1 ¼ miles. Although common in steel practice, the transportation of blister copper in this form had not previously been attempted and a preliminary study of the various factors involved was therefore necessary. For this purpose, a series of experiments was made in which molten copper, removed at different stages during the furnace cycle, was held in a small portable holding furnace. This vessel was essentially a refractory-lined steel cylinder provided with ports for filling and emptying, heated by an oil burner. Dimensions of the steel shell were 3 ft. 10 in. diameter by 7 ft. 3 in. long, and thickness of refractories depended on the design and combination used for the particular experiment. The vessel was filled with approximately 2 ½ tons of copper at a predetermined temperature, the lining having been preheated to a definite point by means of an oil burner. All openings were well luted and temperature readings were made every 15 min. by means of an immersion-type thermocouple. In this manner the rate of heat loss resulting with different refractory design could be developed. The ratio of exterior surface to weight of metal was taken into consideration in comparing the experimental results with what might be expected for a full-sized unit, and observations were also made on type and degree of slag accretion. It was not possible to get as much information on this latter point as desirable, but all evidence showed that the problem would be control of slag build-up rather than attack on refractories. From the information derived, and in consultation with the engineering staff of the supplying company, an order was placed for the first

Jan 1, 1938

By Karen Mikkola, Gerald Luttrell, Jaisen Kohmuench, Glen Oswald, Michael Mankosa, Tracy Westerfield

Hydraulic separators are commonly used for particle size classification and gravity concentration of minerals and coal. Unfortunately, the efficiency of these processes can be quite low due to poor equipment design and variations in feed consistency. To help alleviate these problems, an industry-driven R&D program has been undertaken to develop a new generation of hydraulic separators that are more efficient and less costly to operate and maintain. Two of the most promising technologies, the CrossFlow and HydroFloat separators, have now been tested at industrial sites. The data obtained from these sites have been used to illustrate the potential performance improvements that can be realized through the application of these high-efficiency separators.

Jan 1, 2005

By William C. Geitz

"Lightning has always posed a serious threat to blasting operations, especially wkhin the mining and construction industries and operations involving the manufacture, transport, storage and handling of explosives. In recent years, technological advancements in communications systems and microprocessors have significantiy improved the accuracy and efflliency of lightning detection and warning instrumentation. These advancements have increased the availabilii of highly reliable,accurate and affordable systems for use within the explosives arena."

Jan 1, 1991

By L. D. Smith

"This paper examines the impact of the various assumptions that go into an economic evaluation, and shows how these can be combined to show an exciting result that may not really exist. An example of an embellished case (the kind that one frequently sees when projects are being promoted) is developed and the cumulative impact is analyzed to show the actual project underneath. The paper also points out some areas to watch for overly optimistic assumptions such as prices, inflation, and debt. The concept of a “bare bones” base case is proposed (constant metal prices, constant dollars, no inflation, no debt, no interest, on a project basis, after tax) as a common reference point.As well, the discount rate is examined as one of the fundamental means of reflecting risk in discounted cash flow evaluations. Current industry practice is discussed, and a methodology for the analysis of risk levels is proposed that assesses the constituent components of the discount rate: real interest, mineral project risks, and country risk."

Jan 1, 2002

By Robb L. Swenson

Construction of foundations for the Skyway Segment of the San Francisco Oakland Bay Bridge required innovative techniques due to the mass of the structures being inserted and the unique subsurface of the Bay. Twenty of the pier structures required large sheet pile cofferdams. Eight other foundations were installed in open water without cofferdams at the deeper part of the Bay. This narrative will present the initial planning, as well as the stages of installation, for each type of foundation. The first section will discuss foundation constructability modifications made during the initial planning phases of the project. Considerable effort was expended by Caltrans, the owner, T.Y. Lin the designer, and KFM (Kiewit/FCI/Manson) the contractor in modifying the design to assure that required tolerance would be maintained during the installation of the foundations. The final section will describe the steps required for installation including: initial access dredging, installation of cofferdams, preparation required to install the footing boxes, footing box installation, foundation support pile installation, and pile to box connections.

Jan 1, 2005

By L. Lehasa

The purpose of the project was to investigate the challenges faced by Khutala Colliery pertaining to underground road construction and maintenance. Furthermore the influence of these challenges on productivity and safety requirements were taken into consideration. The operating standards required for the construction and maintenance of the 2 seam road transport infrastructure was investigated, together with reasons why the standards of operating procedure are not met. The Code of Practice put in place by Khutala Colliery was used to view the standard operating procedures. Leading practices on underground road construction were researched. The project aims to discover the gaps that Khutala Colliery must bridge to implement enhanced practices with regards to underground road construction. During the period of study, observations were carried out to determine whether the road construction standards of operating procedure were being adhered to at all times for both road construction and road maintenance. Khutala Colliery has put in place a traffic management plan, which includes safety practices and work policies that must be adhered to while travelling on underground transport roads.

Jan 1, 2012

By M. Newton

Optimization and sensitivity analysis of mineable economic volumes have been standard practise for open pits for many years now, and more recently software has become available to apply techniques for delineating mineable reserves for underground mines. In general these techniques have been applied to a single resource model to quantify mineable tonnes and grade for underground mining. However by using multiple conditionally simulated models both the risk associated with the mining parameters and the risk associated with variations in grade, tonnes and profit can be quantified. Using suitable software the mine planner can then easily and quickly define and compare alternative designs to assess and improve the robustness of and the confidence in the final design.

Jan 1, 2007

By M. Jeffrey

This study investigated the elution of precious and toxic metals from activated carbon. Gold and mercury are of primary interest, due to their value and environmental impact respectively. A laboratory elution rig was commissioned to simulate industrial Zadra and AARL carbon elution conditions. Mercury was found to elute most effectively in strong caustic cyanide solutions; gold was found to elute most effectively in hot low ionic strength solutions. As cyanide decomposes on contact with activated carbon at high temperatures, optimum elution conditions for gold conflicts with those for mercury?no practical compromise in conditions was found. However, sequential elution allowed reasonable recovery of both metals. Ongoing work is looking at the deportment of other metals under elution conditions.

Jan 1, 2009

By Henry Kreisinger, WALTER T. RAY

In its investigation of more efficient methods for utilizing the coals and lignites in the United States, to the end that waste might be avoided, the value of low-grade coals increased, and the life of the nation's fuel resources prolonged, the technologic branch of the United States Geological Survey carried on a study of the factors involved in the manufacture and use of briquets, including the suitability of various coals for briquetting, the cheapest and most satisfactory binders, and the furnace behavior and evaporative efficiency of briquetted fuel. The investigations had their beginning in the work done at the coaltesting plant at the Louisiana Purchase Exposition, St. Louis, Mo., in 1904, and were continued at St. Louis and later at Norfolk, Va. Accounts of various tests and statements of the conclusions to be drawn from them have appeared in a number of bulletins. a In connection with the work at Norfolk, comparative steaming tests were made in stationary, marine, and locomotive boilers with run-ofmine coal and the same coal formed into briquets of two sizes. The tests in a locomotive boiler that are described in detail in this bulletin were undertaken to add cumulative evidence to work done at other places. They were made possible through the courtesy of the Seaboard Air Line Railway Company in supplying both the locomotive and the coal used. During the trials the locomotive stood on a side track in the shop yards of the railway company at Portsmonth, Va. No running tests were made.

Jan 1, 1911